In the mid-1970s a Michigan man charged with shooting and killing his wife was judged ''not guilty by reason of insanity.'' Yet after 53 days of treatment in state mental health facilities, he was considered well enough to be put back on the street. A ruling by the state's highest court confirmed that those judged innocent under the insanity plea could not be kept in institutions once they have recovered.
That was the prod that led Michigan in 1975 to adopt an additional verdict option of ''guilty but mentally ill'' (or GBMI, as lawyers are now fond of calling it). While recognizing the defendant's need for mental treatment, this verdict does not excuse him from legal responsibility and a specific prison sentence for the crime.
Since Michigan took the lead, Indiana, Illinois, New Mexico, Kentucky, and Georgia have followed. Eighteen more states are weighing adoption of the verdict. And in the aftermath of public outrage at the ''not guilty by reason of insanity'' verdict in the trial of presidential assailant John W. Hinckley Jr., Congress is considering a similar provision in federal criminal law.
The new option is hotly controversial. Defense lawyers, some psychiatrists, and many civil libertarians tend to be critical. They suggest that jurors will latch onto it as an easy ''out,'' and many cases that should, in effect, be dismissed because of defendants' mental problems will instead result in convictions. An American Bar Association task force on mental health standards and criminal justice has been working on reform of the insanity defense for two years. An early draft of its recommendations argues that the ''guilty but mentally ill'' verdict is ''misleading.''
''It's a way for society to push the problem under the rug, forcing the correctional system, already subject to strained resources, to decide what ought to be done with the defendant,'' says Dr. Ingo Keilitz, director of the Institute on Mental Disability and Law for the National Center for State Courts. ''The problem . . . is then no longer up front and visible before the courts and jury . . .''
Proponents of the ''guilty but mentally ill'' option tend to describe its virtues in terms of fairness and added protection for society.
''I think the Michigan law is keeping the people off the streets that should be kept off,'' says Paul Rosenbaum, a lawyer and former state representative, who sponsored the Michigan legislation. ''Psychiatry at its best isn't an exact art,'' he said. ''This is one way of closing that loophole.''
''My concern is with community safety, and I think the new verdict option is working very well,'' agrees Jim Shonkwiler, executive director of the Prosecuting Attorneys Association of Michigan.
He says the psychiatric division of the Michigan Department of Corrections reports that about 20 such verdicts are rendered each month under state law, compared with an annual total of only 30 two years ago. He notes that sometimes defendants plead guilty voluntarily under the verdict. They see it as combining admission of the deed with a lack of full responsibility for it because of mental illness. ''It seems to offer some excuse,'' Mr. Shonkwiler says.
Terrance Boyle, chief of the criminal division of the Wayne County (Detroit) prosecutor's office, says that since the new law took effect, about 40 percent of the ''innocent by reason of insanity'' pleas have instead ended in a ''guilty but mentally ill'' verdict from the jury. If judged innocent because of insanity , he says, many of the same defendants would have been back on the street within 60 days.
''The new verdict option is a very good one for jurors, and it's removed a lot of the confusion . . . over mental illness by offering them a choice,'' Mr. Boyle says.
Not everyone in Michigan, of course, agrees. Many lawyers, who consider the present law more than adequate to cover a broad range of criminal cases, stress that discriminating jurors nationwide rarely grant the insanity plea as it is. Therefore the defense is rarely sought, they say.
''I think the 'guilty but mentally ill' verdict is a sop,'' says Leo Farhat, a Lansing lawyer and former president of the Michigan State Bar. ''It's an attempt to set a plateau of less than insanity, yet of not full responsibility for one's actions. Many of us were skeptical from the start on the need for that kind of verdict.''
''I don't think it's necessarily a bad statute, but in operation it's a disaster,'' says Ivan Barris, a Detroit criminal defense lawyer. ''The Legislature didn't appropriate any money for psychiatric treatment, (so) it doesn't mean anything. It's just the same as going to jail on a guilty verdict.''
But proponents counter that this dollars-for-treatment issue misses the point.
''The focus should be on providing that treatment and not on attacking the verdict option, which is helping keep those who have committed crimes and are responsible for keeping them . . . off the street,'' says Mr. Shonkwiler.
Mr. Boyle stresses that 80 percent of those judged ''guilty but mentally ill'' under Michigan law are later diagnosed by mental health authorities as having no mental illness.
The so-called fourth verdict - after guilty, not guilty, and not guilty by reason of insanity - is too new in most other states to have acquired a track record. Indiana approved it in 1980 after a dramatic incident in Indianapolis in which a man who considered himself wronged in a real estate transaction held a mortgage banker hostage for several days with a sawed-off shotgun. He pleaded and received a verdict of ''not guilty by reason of insanity'' but is still being held, pending mental tests, which he refuses to take.
''The jury can still choose that 'not guilty' option - we're just adding another possibility for it to hang its hat on,'' says John Donaldson, a Lebanon, Ind., lawyer who as a state representative was the chief sponsor of the legislation in his state. He notes that in addition to offering the new verdict, the bill in Indiana shifted the burden of proof from the prosecution, which usually must prove beyond a reasonable doubt that the defendant was sane at the time of the crime, to the defense, which must prove that the defendant is mentally ill.
So far seven states have amended their criminal statutes to shift the burden of proof from prosecution to defense this way. Though the defense is expected to have an easier time proving that a client is insane or mentally ill than the prosecution is of proving him sane, many civil libertarians are concerned about the implications for the ''innocent until proven guilty'' premise underlying the American judicial system.
Kentucky and Georgia are the two newest additions to the roster of states adopting the ''guilty but mentally ill'' verdict. Their laws took effect just this week.
State Rep. Larry Walker of Perry, Ga., principal sponsor of the legislation in that state, says that opposition came largely from groups interested in criminal defense, but that leaders of both the state prison and mental health systems opposed it on grounds it would increase their expenses. Mr. Walker agrees that the new verdict will probably lead to more convictions.
''I don't think it's going to work,'' says Frand Haddad Jr., a Kentucky lawyer and past president of the National Association of Criminal Defense Attorneys. ''It changes the whole concept of culpability . . . but it doesn't allow the courts to do anything they can't already do under present law.''